1. Field of the Invention
The present invention relates generally to sensors and, more particularly, to systems and methods for integrated electrochemical, electrical and/or optical detection.
2. Description of Related Art
Electrochemical sensors have been used in various chemical and medical applications to detect concentrations of biological analyte. However, the inventors hereof have recognized that electrochemical detection is not without problems. For example, when an insufficient concentration of analyte is provided, the current flowing between working and counter electrodes of the sensor is undetectable. Because the amount of analyte detected is directly proportional to the current flowing through the sensor, small analyte concentration can result immeasurable.
Electrical sensors have also been used to determine analyte concentrations by detecting molecular binding-induced conductance or impedance changes in electrical materials (e.g., silicon, conducting polymers, and carbon nanotubes). Unfortunately, the inventors hereof have also identified many drawbacks of this technique. For instance, in addition to their large dimensions and high manufacturing costs, electrical sensors are generally highly dependent on the environment (e.g. ionic strength), less specific and less accurate.
The referenced shortcomings are not intended to be exhaustive, but rather are among many that tend to impair the effectiveness of previously known techniques as recognized by the present inventors. These problems are sufficient to demonstrate that the methodologies appearing in the art have not been satisfactory, and that a significant need exists for the techniques described and claimed in this disclosure.